So I picked up the game for PC today after having spent months trying to play it on PS3 and then moving on to the 360 version for a while.

When I reached Whiterun, I went into the Bannered Mare and found a buxom woman leaning against pillar in the middle of the room, named Sarah. When I clicked on her to talk to her, it gave me the option to take her on as a follower.

I've never seen this character mentioned in Follower guides and I've never seen her in the console versions of the game. Who is she and where did she come from?

Wow ive never heard of her

I've never seen a Sarah in mine.

Maybe she's from a mod.
There's no follower called Sarah.

It sounds like the http://skyrim.nexusmods.com/downloads/file.php?id=16461 mod to me.

It would be a save guess to say that it is without a doubt...a mod.

If it's from a mod, I'd like to know which one has put her in the game, as I've only got a small handful of them installed, and they're mostly to improve ambiance/blood effects and the like. She's fully voice acted (she sounds like the same woman who plays Lydia, but she has different dialog from Lydia).

Here's a list of my Data Files:

High Res Texture Pack 01
High Res Texture Pack 02
Arrowsmith v3b
Stones of Barenziah Quest Markers
Enhanced Blood Textures
Realistic Ragdolls and Force
House Map Markers
Sound of Skyrim - The Dungeons
Sounds of Skyrim - The Wilds
Conjure Rideable Ethereal Horse
Killmove +
Void Armor +
Followers Equip From Inventory Always
Naturalistic Werewolves
Enhanced Soundtrack Part 1 & 2
SCARY SKYRIM RETEXTURE
Essential Followers Lite
More Dynamic Shadows and Striping Fixed

Only two of the mods I have are specifically to do with Followers, but neither of them seemed to have anything to do with putting a new follower in the game when I downloaded them.

A wild guess but.... Essential Followers Lite? Lol =p

What makes you think that would be the one?

All that mod does is make your Followers essential (ie: stops them from dying). Nothing in the mod description indicates a new character.

I found it. This comes from your http://skyrim.nexusmods.com/downloads/file.php?id=13770 mod. From the Nexus page: "Added Custom Follower, Sarah to the BanneredMare in Whiterun."

Ah okay, thanks Wyrd. That was the next mod I was going to check, I just hadn't made it back to the Workshop yet. Cheers.

Was she voiced?